Blind rivet, rivet pin, holding device, method for producing a blind rivet and method for creating a riveted joint

ABSTRACT

The invention relates to a blind rivet, a rivet pin, a holding device, a method for producing a blind rivet and a method for creating a riveted joint which enables a permanent joint to be produced between several workpieces in one working cycle.

STATE OF THE ART

[0001] The invention involves a blind rivet, a rivet mandrel, a mountingdevice, a process for manufacturing a blind rivet and a process formaking a riveted joint according to the generic concept of claim 1,claim 11, claim 14, claim 15 and claim 16.

[0002] A blind rivet (open-end blind rivet, closed-end blind rivet) isused to create an inseparable connection between several workpieces,whereby in order to set the rivet, only one side of the workpiece mustbe accessible. Usually, before the blind rivet is inserted, a hole mustbe pre-drilled. This practice, however, requires an additional work stepand in addition, is time-consuming.

[0003] In order to minimize this time expense, an open-end blind rivet(G 93 02 633) is provided with a tip that allows it to penetrate throughthe workpiece and anchor the blind rivet in a work operation using adevice. It is disadvantageous in this process that only relativelythin-walled and soft plate materials can be penetrated. This is, on theone hand, based on the blind rivet manufacturing process, in which thetip of a blind rivet is usually created by massive forming (molding).This process, however, does not lead to sharp edges, but instead torounded off edges of the tips, which thus only push through theworkpieces, but can not cut through them. On the other hand, thematerial used, for example, is not able to handle the impact forcesnecessary for the penetration of harder and/or thicker materials.

THE INVENTION AND ITS ADVANTAGES

[0004] The blind rivet according to the invention with thecharacterizing properties of claim 1, on the other hand, has theadvantage that within one work step, a penetration through theworkpieces and a subsequent anchoring of the blind rivet occurs. Forthis purpose, in the blind rivet according to the invention, the rivetshaft is constructed in a cup-shape (closed-end blind rivet) and the endof the rivet shaft away from the the rivet head-side is constructed as atip and/or with a sharp edge. In this way, the penetration of theworkpieces is made easier and also, it is possible to bore throughharder and thicker materials.

[0005] According to an advantageous embodiment of the invention, the tipis ground to form a sharp edge.

[0006] According to another advantageous embodiment of the invention,the tip is cut to form a sharp edge.

[0007] According to another advantageous embodiment of the invention,the tip is cut to form a sharp edge and then ground after that.

[0008] According to another advantageous embodiment of the invention,the tip has an angle between 10° and 70°.

[0009] According to another advantageous embodiment of the invention,the tip has a cross-section that is at least triangular, a partitionwall, a dagger shape, or the like. In this way, the cut edges end in oneor more points on the outer end of the end of the mandrel.

[0010] According to another advantageous embodiment of the invention,the rivet head collar of the blind rivet has an undercut on the sidethat faces the workpiece.

[0011] According to another advantageous embodiment of the invention,the rivet head collar of the blind rivet is in the shape of a sphere. Inthe use of mounting devices in shooting devices or the like, therequirements of the mounting device and thus the material wear isreduced by these rounded-off areas.

[0012] According to another advantageous embodiment of the invention,the rivet head collar of the blind rivet is provided with a sealingelement. In this way, the joint of the workpieces riveted with the blindrivet is impermeable to liquid and gas.

[0013] According to another advantageous embodiment of the invention,the degree of hardness of the rivet mandrel is at least 600 N/mm². Inthis way, a deformation of the rivet mandrel by the impact is prevented.

[0014] The rivet mandrel of a blind rivet according to the inventionwith the characterizing properties of claim 11 has the advantage, asopposed to the state of the art, that, as in the key-lock principle, thefree mandrel end (11) of the rivet mandrel (2) is shaped in a radiallyform-fit manner with the tool used to set the blind rivet (shootingdevice, blind rivet setting device, or the like). By the special designof the end of the mandrel, an optical interaction between the blindrivet and the special tool required to set the blind rivet is ensured.In this way, the insertion forces act in the direction and along therivet mandrel axis.

[0015] According to an advantageous embodiment of the invention, thefree mandrel end is constructed as a centrally symmetrical elevation orrecess (cone, spherical segment, pyramid, spherical cap, indentation, orthe like). In this way, a force acting on the mandrel end is at leastpartially guided further in the direction of the rivet mandrel centeraxis.

[0016] According to another advantageous embodiment of the invention,the rivet mandrel is tapered towards the mandrel end or constructed sothat it expands.

[0017] The mounting device according to the invention, of a tool(shooting device, blind rivet setting device, or the like) for thefixing of a blind rivet, with the characterizing properties of claim 14,has, as opposed to the state of the art, the advantage that thethrough-put opening of the mounting device has a ring, or the like,through the opening of which the blind rivet can be received.

[0018] According to an advantageous embodiment, the ring integrated inthe mounting device is manufactured mostly out of rubber, or the like,and can thus be flexibly fit to different blind rivets, in order toprevent them from falling out, for example, from out of the shootingdevice.

[0019] The process according to the invention for manufacturing a blindrivet, in particular, a blind rivet with a tip with the characterizingproperties of claim 16, provides for a sharpening of the rivet mandrelor the rivet shaft. This sharpening is done after or during the processsteps customary in the course of machine manufacturing (e.g. cuttinginto lengths, pre-clenching, putting together of the individual parts)by cutting and/or grinding.

[0020] The process according to the invention for making a rivetedjoint, in particular using a device suitable for this purpose (shootingdevice, blind rivet setting device, or the like), with thecharacterizing properties of claim 18, provides that the forces of thetool (shooting device, blind rivet setting device, or the like) actingin the setting direction on the rivet mandrel, which cause the workpieceto be bored through until the stopper, are guided at least partially inthe direction and along the rivet mandrel center axis. By this transferof forces, even harder workpieces can also be bored through.

[0021] According to an advantageous embodiment of the process accordingto the invention, a pin transfers a force acting by an impact orstriking on the rivet mandrel, which makes it possible to the go throughworkpiece.

[0022] According to a related embodiment of the process according to theinvention, the pin is tapered on the side that faces the rivet mandrel,provided with an indentation (spherical cap) and/or another constructionfunctioning for the purpose of centering.

[0023] According to another advantageous embodiment of the processaccording to the invention, the device (shooting device, blind rivetsetting device) for fixing the rivet head has a mounting device with aring made of rubber or the like. By fixed clamping of rivet head usingthe ring, a falling out of the blind rivet out of the device isprevented.

[0024] According to another advantageous embodiment of the processaccording to the invention, the boring of the workpiece is done as acut. This cutting makes easier the penetration of the workpieces.

[0025] Additional advantages and advantageous embodiments of theinvention can be ascertained from the following description, the drawingand the claims.

DRAWING

[0026] Embodiment examples of the object of the invention are describedin greater detail in the following. Shown are:

[0027]FIG. 1 a side view of a closed-end blind rivet with tip,

[0028]FIG. 2 a section view of the closed-end blind rivet with tip fromFIG. 1,

[0029]FIG. 3 a three-dimensional view of the closed-end blind rivet withtip from FIG. 1,

[0030]FIG. 4 a side view of a closed-end blind rivet with tip andsealing ring,

[0031]FIG. 5 a section view of the closed-end blind rivet with tip andsealing ring from FIG. 4,

[0032]FIG. 6 a three-dimensional view of the closed-end blind rivet withtip and sealing ring from FIG. 4,

[0033]FIG. 7 a side view of an open-end blind rivet with sharpened rivetmandrel,

[0034]FIG. 8 a section view of the open-end blind rivet with sharpenedrivet mandrel from FIG. 7,

[0035]FIG. 9 a side view of an open-end blind rivet with sharpened rivetmandrel and with an indented mandrel end and,

[0036]FIG. 10 a section view of an open-end blind rivet, which is fixedin a mounting device of a shooting device (not shown).

DESCRIPTION OF THE EMBODIMENT EXAMPLE

[0037] The blind rivet shown in FIG. 1 is a closed-end blind rivet andessentially consists of a rivet mandrel 2 and a closed-end rivet shaft5. The rivet shaft 5 is subdivided into the rivet head 6 and a closinghead 8. The end of the rivet shaft 5 away from the rivet head is shapedinto a tip 9. This tip makes it possible for the workpieces to bepenetrated without the necessity for a pre-drilling. By a subsequentpull of the rivet mandrel 2 in the direction opposite the impactdirection, the rivet shaft 5 and the closing head 8 become deformedresulting in a joining of the workpieces.

[0038] This deformation is brought about in a closed-end blind rivetthrough the rod head 3 shown in FIG. 2, which is pulled in the directionof the rivet head 6 in order to anchor the closed-end blind rivet. Theriveted joint is thus made on the one side of the workpieces to bejoined by the deformation of the rivet shaft 5 and the closing head 8and on the other side of the workpieces by the rivet head 6, whose edgehas a rivet head collar 4. After the joint has been made, the targetbreaking point 1 makes possible a separation of the rivet mandrel 2.

[0039] In FIG. 3, a three-dimensional diagram of the closed-end blindrivet is shown. In this diagram, the free end of the rivet mandrel 2 isdepicted clearly as a mushroom head. Depending on the special tool used(shooting device, blind rivet setting device, or the like), however, inorder to achieve an optimal form-fit, other shapes (pyramid, cone,indentation, or the like) of the mandrel end 11 are possible.

[0040] The embodiment example of a closed-end blind rivet shown in FIGS.4, 5 and 6 is distinguished from the embodiment example shown in FIGS.1, 2 and 3 by the sealing element 7, which after the connection, liesflush between the workpiece and the rivet head 6 and thus causes aliquid and gas impermeable seal.

[0041] The blind rivet shown in FIG. 7 is an open-end blind rivet andconsists essentially of a rivet mandrel 2 and a rivet tube. In thiscase, the rivet mandrel 2 is shaped into a tip 9. This tip 9 makespossible the penetration of the workpieces without a pre-drilling beingnecessary. By a subsequent pull of the rivet mandrel 2 in the directionopposite the impact direction, the rivet shaft 5 and the closing head 8are deformed resulting in a riveted joint of the workpieces. The mandrelend 11 has a rounded-off shape. However, in order to obtain an optimalfit to the tool used for processing (shooting device, blind rivetsetting device, or the like), other shapes (pyramid, cone, indentation,or the like) of the end of the mandrel 11 are possible.

[0042] The undercut 12 shown in FIG. 8 functions for the better supportof the processed blind rivet on the workpiece. This undercut is alsoconceivable on closed-end blind rivets.

[0043] The mandrel end 11 shown in FIG. 9 is indented in the shape of aspherical cap. However, other indentations 13 of the mandrel end 11 arealso possible. By this design, the force of the pin is centered andguided into the rivet mandrel interior when the pin hits or strikes theend of the mandrel 11.

[0044]FIG. 10 shows a section view of an open-end blind rivet, which isfixed in a mounting device of a shooting device (not shown). Thespherical, rounded-off shape of the rivet head collar 4, which makes itpossible for the opening of the flexible ring 14 preferably made out ofrubber to fit, in order to become clamped fixed behind so that the blindrivet is secured against falling out, is advantageous. By therounded-off shape of the rivet head collar 4, the wear on the ring 14 isminimized. The spherical, rounded-off shape of the rivet head collar 4is also conceivable on a closed-end blind rivet. In order to fix theblind rivet in the mounting device, other embodiments are alsoconceivable, in addition to the ring 14 that forms the opening, possiblyeven several structural parts.

[0045] All of the characteristics depicted in the description, thefollowing claims, and the drawings can be essential to the inventionboth individually as well as in any desired combination with each other.

[0046] Reference Number List

[0047]1 Target breaking point

[0048]2 Rivet mandrel

[0049]3 Rod head

[0050]4 Rivet head collar

[0051]5 Rivet shaft

[0052]6 Rivet head

[0053]7 Sealing element

[0054]8 Closing head

[0055]9 Tip

[0056]10 Mandrel end

[0057]11 Undercut

[0058]12 Indentation

[0059]14 Ring

[0060]15 Part of the shooting device

1. Blind rivet for joining workpieces with a rivet mandrel (2) that hasa target breaking point (1) and a mandrel end (11), with a rivet head(6) and rivet shaft (5) arranged coaxially to the rivet mandrel (2),with a rod head (3) located on the rivet mandrel (2) on the targetbreaking point side and with a rivet head collar (4) that is arranged onthe rivet shaft (5) and is to be set on a workpiece, characterized inthat the rivet shaft (5) is constructed so that it has a closed-end andthe end that faces away from the mandrel end (11) of the blind rivet isconstructed as a tip (9) and/or with a sharp edge.
 2. Blind rivetaccording to claim 1, characterized in that the tip (9) is ground sothat it has a sharp edge.
 3. Blind rivet according to claim 1,characterized in that the tip (9) is cut so that it has a sharp edge. 4.Blind rivet according to claim 1, characterized in that the tip (9) iscut so that it has a sharp edge and after that it is ground.
 5. Blindrivet according to one of the preceding claims, characterized in thatthe edges of the tip (9) have an angle between 10° and 70°.
 6. Blindrivet according to one of the preceding claims, characterized in thatthe tip (9) has a cross-section that is at least triangular, a partitionwall, a dagger shape, or the like.
 7. Blind rivet according to one ofthe preceding claims, characterized in that the rivet head collar (4)has an undercut (12) on the side facing the workpiece.
 8. Blind rivetaccording to one of the preceding claims, characterized in that therivet head collar (4) is formed in the shape of a sphere.
 9. Blind rivetaccording to one of the preceding claims, characterized in that asealing element (7) is applied on the workpiece-side part of the rivethead (6).
 10. Blind rivet according to one of the preceding claims,characterized in that the degree of hardness of the rivet mandrel (2) isat least 600 N/mm².
 11. Rivet mandrel (2) in particular, of a blindrivet (closed-end blind rivet, open-end blind rivet) according to one ofthe claims 1 to 10, characterized in that the free mandrel end (11) ofthe rivet mandrel (2) is shaped in a radial form-fit manner with thetool (shooting device, or the like) used to set the blind rivet and thesetting forces act in the direction and along the rivet mandrel axis.12. Rivet mandrel (2) according to claim 11, characterized in that thefree mandrel end (11) is constructed as a centrally symmetric elevationor recess, such as a cone, spherical segment, pyramid, spherical cap,indentation (13) or the like.
 13. Rivet mandrel (2) of a blind rivetaccording to claim 11 or claim 12, characterized in that the rivetmandrel (2) is shaped tapering or expanding towards the mandrel end(11).
 14. Mounting device of a tool (shooting device, blind rivetsetting device, or the like) for affixing a blind rivet, in particular,according to one of the claims 1 to 13, with a through-put opening toreceive the blind rivet, characterized in that, a ring (14) providedwith an opening to receive the blind rivet is arranged in thethrough-put opening.
 15. Mounting device according to claim 14,characterized in that the ring (14) is made of rubber or the like. 16.Process for manufacturing a blind rivet with the process steps customaryin the course of machine manufacturing, namely cutting into lengths,pre-clenching, putting together of the individual parts, etc., inparticular according to one of the claims 1 to 13, characterized inthat, the blind rivet is provided with a tip (9) and before or after theputting together of the required individual parts (rivet mandrel (2),rivet shaft (5)) the sharpening operation of the rivet mandrel (2) orthe rivet shaft (5) is done by cutting and/or grinding.
 17. Process forsetting a blind rivet that consists of a rivet mandrel (2) having atarget breaking point (1), a rivet head (6) and a rivet shaft (5) thatis made closed-ended or open-ended, a rod head (3) located at the targetbreaking point of the rivet mandrel (2), and a rivet head collar (4) tobe set on a workpiece, in particular, according to one of the claims 1to 13, using a device suitable for this purpose (shooting device, blindrivet setting device), by which the driven blind rivet bores, until thestopper on the rivet shaft side, through one or more workpieces to beconnected, in order to, in the next process step, then pull, whilesimultaneously holding the rivet head (6), the rivet mandrel (2) againstthe setting direction, whereby an expansion (closing head) that createsa joint is formed because of the force prespecified for the targetbreaking point (1) being exceeded until the separation of the rivetmandrel (2), on the side of the rivet shaft (5) opposite the rivet head(6), characterized in that, the forces of the device acting in thesetting direction on the rivet mandrel (2), are guided at leastpartially in the direction and along the rivet mandrel axis.
 18. Processaccording to claim 17, characterized in that the force acting on therivet mandrel (2), which causes the setting of the rivet through theworkpiece, is transferred through a pin onto the rivet mandrel (2). 19.Process according to claim 18, characterized in that the pin tapers onthe side facing the rivet mandrel (2), is provided with an indentation(spherical cap) and/or has a different design that functions to centerit.
 20. Process according to one of the claims 17 to 19, characterizedin that the rivet head (6) is guided in a mounting device which holdsthe blind rivet elastically fixed.
 21. Process according to one of theclaims 17 to 20, characterized in that the workpiece is bored through asa cut.